Observed Signal · Oct 13, 2026 · Technical Release · Source: https://developer.chrome.com/static/blog/feed.xml · Impact: 3/5 · Sentiment: Positive
Chrome 155 introduces new Tabs Split View API for extensions
Chrome 155 introduces the new Split View API, allowing extensions to programmatically detect, create, and manage built-in split views in the browser. Developed with Mozilla and other browser vendors in the WebExtensions Community Group, the API integrates with the Tabs API and requires no additional permissions. Extensions can now create split views using the `splitWithTabId` parameter or the `createSplit` method, and unsplit them via the `unsplit` method. Previously, extensions had to use brittle workarounds like resizing native windows or embedding iframes. The API was announced in October 2026, following the native split view feature introduced in Chrome 145 in February 2026. This enhances productivity workflows by enabling more robust multitasking extensions.
This release enhances Chrome's extension capabilities, directly impacting the AdTech ecosystem by enabling more robust multitasking extensions that can improve productivity and user engagement, though it does not directly alter advertising technology or data flows.
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Key Takeaways & Evidence Grounding
- Chrome 145 introduced native Split View in February 2026.
- Chrome 155 introduces the new Split View API.
- Developed with Mozilla and other browser vendors in the WebExtensions Community Group.
- The API is part of the browser.tabs namespace and requires no permissions.
- Extensions can create split views via 'splitWithTabId' or 'createSplit' and unsplit via 'unsplit'.
Connected Companies & Entities
1 Entity mapped“Developed in close collaboration with Mozilla and other browser vendors in the WebExtensions Community Group.”
Related Market Signals & Shifts
Recent verified developments and strategic activity across this market segment.
Chrome adds vertical tabs and refreshed Reading Mode
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Chrome I/O 2026: Web Extensions Updates
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